Activating Compound | Comment | Organism | Structure |
---|---|---|---|
cyclic-di-GMP | BcsA contains a PilZ domain within its C-terminal, intracellular domain and its activity is strongly stimulated by the bacterial secondary messenger cyclic-di-GMP | Cereibacter sphaeroides |
Cloned (Comment) | Organism |
---|---|
recombinant expression of His-tagged subunits BcsA and B in Escherichia coli strain C43 | Cereibacter sphaeroides |
Crystallization (Comment) | Organism |
---|---|
purified recombinant native and selenomethionine -labeled complex of BcsA and BcsB containing a translocating polysaccharide, from 30% PEG 200, 0.1 M MES, pH 6.5, and 50 mM NaCl at 4°C, 7 days, X-ray diffraction structure determination and analysis, modeling, overview | Cereibacter sphaeroides |
Localization | Comment | Organism | GeneOntology No. | Textmining |
---|---|---|---|---|
inner membrane | cellulose synthases are membrane-embedded glycosyltransferases. BcsB is a periplasmic protein that is anchored to the inner membrane via a single, C-terminal transmembrane helix. BcsA and BcsB are fused | Cereibacter sphaeroides | - |
- |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
UDP-glucose + [(1->4)-beta-D-glucosyl]n | Cereibacter sphaeroides | - |
UDP + [(1->4)-beta-D-glucosyl]n+1 | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Cereibacter sphaeroides | Q3J125 | - |
- |
Purification (Comment) | Organism |
---|---|
recombinant His-tagged native and selenomethionine -labeled subunits BcsA and B from Escherichia coli strain C43 by nickel affinity chromatography and gel filtration | Cereibacter sphaeroides |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
UDP-glucose + [(1->4)-beta-D-glucosyl]n | - |
Cereibacter sphaeroides | UDP + [(1->4)-beta-D-glucosyl]n+1 | - |
? |
Subunits | Comment | Organism |
---|---|---|
dimer | BcsA and BcsB form a 1:1 stoichiometric complex spanning approximately 150 A perpendicular and 55 A parallel to the membrane. The complex is divided into a cuboid-shaped membrane-spanning region sandwiched between large cytoplasmic and periplasmic domains. BcsA contains four N-terminal and four C-terminal transmembrane-helices separated by a large intracellular loop (4/5-loop) that forms a GT-domain (aa 128 to 368). transmembrane domains 3-8 form a narrow channel for the translocating polysaccharide and BcsA's intracellular C-terminus (aa 575 to 759) contains a 6-stranded beta-barrel and a highly curved alpha-helical region that attaches the beta-barrel to the GT-domain. BcsB is a dome-shaped, beta-strand rich, periplasmic protein. Its N-terminal region forms the tip of the dome, whereas the C-terminal transmembrane-anchor interacts with BcsA. Two amphipathic helices further stabilize its interaction with BcsA and the periplasmic water-membrane interface. Domain structures. Modeling, overview | Cereibacter sphaeroides |
Synonyms | Comment | Organism |
---|---|---|
BcsA-B | - |
Cereibacter sphaeroides |
inner membrane-associated bacterial cellulose synthase | - |
Cereibacter sphaeroides |
General Information | Comment | Organism |
---|---|---|
additional information | structure of the BcsA-B translocation intermediate revealing the architecture of the cellulose synthase. Subunit BcsA forms a cellulose-conducting channel, modeling for the coupling of cellulose synthesis and translocation in which the nascent polysaccharide is extended by one glucose molecule at a time, overview | Cereibacter sphaeroides |
physiological function | cellulose synthases (CESAs) are membrane-embedded glycosyltransferases, which utilize UDP-activated glucose (UDP-Glc) to processively elongate the nascent polysaccharide in a reaction that inverts the configuration at the anomeric carbon of the newly added sugar from alpha to beta. Cellulose synthesis and transport across the inner bacterial membrane is mediated by a complex of the multi-spanning catalytic BcsA subunit and the membrane-anchored, periplasmic BcsB protein. Structure-function analysis and modeling, overview | Cereibacter sphaeroides |